Grass mowing machines used for golf courses and other areas where a high quality cut is desired include fairway mowers, trim mowers and greens mowers, all of which typically have three or more cutting units mounted to a traction frame. Each cutting unit may be pivotably mounted to a lift arm extending from the frame of the traction vehicle. Each reel cutting unit typically has a width of 18 inches up to 36 inches. Wider cutting units help increase mowing productivity for large wide open areas such as golf course fairways, and narrower cutting units are more useful for mowing where space is limited or restricted, or where terrain is uneven.
Although there exist a wide range of mowing applications, including a variety of different golf course environments, grass mowing machine frames are designed to carry cutting units of a specific width. Wider or narrower cutting units cannot be substituted on the same machine, even if lift arms with suitable lengths are provided. The frame of a grass mowing machine does not provide sufficient gaps between wider cutting units, or provides excessive gaps between narrower cutting units.
As a result, manufacturers, dealers and operators cannot freely substitute different size cutting units on the same grass mowing machine. A grass mowing machine is needed that can carry different width cutting units, and still provide appropriate gaps between the cutting units. It also is desirable to reduce the number of different mowing machine sizes and models that are manufactured, sold and used.